This invention relates to engine control systems of the type which obtains control data by performing map scanning in accordance with the number of revolutions of an engine and the load applied to the engine, and more particularly it is concerned with an engine control system of the type described which is suitable for controlling internal combustion engines, such as gasoline engines for automotive vehicles.
For internal combustion engines (hereinafter engines for short), such as gasoline engines for automotive vehicles, a control system generally referred to as an electronic control type engine control system is known, for example as disclosed in U.S. Pat. No. 4,201,161. This system is designed to monitor the number of revolutions of an engine and the load applied to the engine and scans a map by using the obtained data as parameters, so as to obtain control data on fuel supply and ignition timing that are necessary for controlling the performance of the engine.
The engine control system of the type in which a map is scanned as referred to hereinabove offers the advantage that it responds quickly to changes in engine operating conditions and is capable of admirably coping with a transient condition of the engine, so that engine control can be achieved satisfactorily. However, one problem encountered by this system is that, when the throttle valve is actuated and brought to a condition in which it is nearly fully open, a pulsation appears in the engine torque, with a result that surging occurs in engine speed and spoils riding comfort.